Light microenvironment and single-cell gradients of carbon fixation in tissues of symbiont-bearing corals

TY - JOUR

T1 - Light microenvironment and single-cell gradients of carbon fixation in tissues of symbiont-bearing corals

AU - Wangpraseurt, Daniel

AU - Pernice, Mathieu

AU - Guagliardo, Paul

AU - Kilburn, Matt

AU - Clode , Peta

AU - Polerecky, Lubos

AU - Kühl, Michael

PY - 2016/3/1

Y1 - 2016/3/1

N2 - Recent coral optics studies have revealed the presence of steep light gradients and optical microniches in tissues of symbiont-bearing corals. Yet, it is unknown whether such resource stratification allows for physiological differences of Symbiodinium within coral tissues. Using a combination of stable isotope labelling and nanoscale secondary ion mass spectrometry, we investigated in hospite carbon fixation of individual Symbiodinium as a function of the local O 2 and light microenvironment within the coral host determined with microsensors. We found that net carbon fixation rates of individual Symbiodinium cells differed on average about sixfold between upper and lower tissue layers of single coral polyps, whereas the light and O 2 microenvironments differed ∼15- and 2.5-fold, respectively, indicating differences in light utilisation efficiency along the light microgradient within the coral tissue. Our study suggests that the structure of coral tissues might be conceptually similar to photosynthetic biofilms, where steep physico-chemical gradients define form and function of the local microbial community.

AB - Recent coral optics studies have revealed the presence of steep light gradients and optical microniches in tissues of symbiont-bearing corals. Yet, it is unknown whether such resource stratification allows for physiological differences of Symbiodinium within coral tissues. Using a combination of stable isotope labelling and nanoscale secondary ion mass spectrometry, we investigated in hospite carbon fixation of individual Symbiodinium as a function of the local O 2 and light microenvironment within the coral host determined with microsensors. We found that net carbon fixation rates of individual Symbiodinium cells differed on average about sixfold between upper and lower tissue layers of single coral polyps, whereas the light and O 2 microenvironments differed ∼15- and 2.5-fold, respectively, indicating differences in light utilisation efficiency along the light microgradient within the coral tissue. Our study suggests that the structure of coral tissues might be conceptually similar to photosynthetic biofilms, where steep physico-chemical gradients define form and function of the local microbial community.

U2 - 10.1038/ismej.2015.133

DO - 10.1038/ismej.2015.133

M3 - Journal article

C2 - 26241503

SN - 1751-7362

VL - 10

SP - 788

EP - 792

JO - I S M E Journal

JF - I S M E Journal

ER -